1. Field of the Invention
The present invention relates to an electric part with illumination and, more specifically, to an electric part with illumination which can introduce light from an illuminating member to illuminate an operating member.
2. Description of the Related Art
As an electric part with illumination used for vehicles or the like, structures disclosed in Japanese Unexamined Patent Application Publication No. 9-102234 (hereinafter, referred to as a prior art) and Japanese Unexamined Utility Model Registration Application Publication No. 1-160806 (hereinafter, referred to as another prior art) are known, and the prior art is shown in FIG. 12 to FIG. 15, and another prior art is shown in FIG. 16.
The prior art will be described first. In FIG. 12 to FIG. 15, reference numeral 200 designates an upper case of a case, and reference numeral 210 designates a lower case (or a holder) of the case. An inner partition plate 211 of the lower case 210 includes terminals 212 fixed thereto, and the inner partition plate 211 also includes a light source 220 detachably mounted thereto.
Reference numeral 230 designates an inner case which is a separate member from the upper case 200 and the lower case 210, and reference numeral 240 designates an insulative circuit board. The circuit board 240 is formed of, for example, a printed circuit board (P.C.B). An upper surface of the circuit board 240 is provided with an electrically-conductive conductor by printing.
Reference numeral 250 designates a slider for a four-direction switch. The four-direction slider 250 is disposed so as to be capable of sliding in four directions in the upper case 200 between the inner case 230 and the circuit board 240.
Reference numeral 260 designates an actuator of the four-direction switch. The actuator 260 is supported by the case (the upper case 200, the lower case 210, and the inner case 230) so as to be capable of tilting in four directions for sliding the four-direction slider 250 in four directions.
A lower surface of an engaging portion 261 of the actuator 260 opposes the single light source 220 via a through hole 241 of a small square shape formed on the circuit board 240. The actuator 260 also constitutes a transmitting member for allowing light from the single light source 220 to be transmitted to a mark 281 on a four-direction switching knob 280 described later.
Reference numeral 280 designates the switching knob of four-direction switch. The four-direction switching knob 280 is fixedly fitted to an upper end of a shaft portion 262 of the actuator 260. Reference numeral 290 designates an automatic restoration spring for the four-direction switch.
Reference numeral 300 designates a slider for two-direction switch. The two-direction slider 300 includes an operating rod 301 at a substantially center of an upper surface thereof so as to project integrally upward in the vertical direction. A lower surface of the two-direction slider 300 is integrally provided with four hollow cylindrical storages 302 opening on the bottom sides thereof. The two-direction slider 300 is arranged in the upper case 200 between the upper case 200 and the upper surface of the circuit boards 240 so as to be capable of sliding in the linear direction.
The lower surface of the two-direction slider 300 opposes a conductor 310, described later, through the small rectangular through hole 241 of the circuit board 240. The two-direction slider 300 constitutes a part of two-direction switch, and also constitutes a transmitting member for allowing light from the single light source 220 to be transmitted to a mark 321 of a two-direction switching knob 320 via the light guiding member 310.
The two-direction switching knob 320 is fixedly fitted to an upper end of the operating rod 301 of the two-direction slider 300. The two-direction switching knob 320 includes, for example, a light-transmitting synthetic resin (acrylate resin (PMMA: polymethylmethacrylate)) and formed substantially into an L-shape. The mark 321 having light transmitting property is provided at substantially a center of a top of the two-direction switching knob 320. The above-described mark 321 is illuminated by light from the single light source 220, which is guided by the light guiding member 310, described later, and transmitted through the two-direction slider 300 as the transmitting member.
Reference numerals 350 and 360 designate ball and spring as s switching mechanism. The spring 360 is stored on one side surface of the two-direction slider 300 in an compressed state, while the ball 350 is provided between the spring 360 in the compressed state and s switching groove (not shown) provided on an inner surface of the upper case 200. The switching mechanism retains a state in which the two-direction switching knob 320 and the two-direction slider 300 are positioned at a neutral position, a first position, and a second position, and function to give a tactile feedback of switching operation of the two-direction switching knob 320 and the two-direction slider 300.
Reference numeral 370 designates a contact of the two-direction switch. The two-direction contact 370 includes four coil springs 371 for contact points, two plate contacts 372, and four contact point balls 373. The four contact balls 373 of the two-direction contact 370 are constantly in press-contact with the circuit board 240 via the plate contacts 372 by a coil spring 371, and is moved in two linear directions on the circuit board 220 via the two-direction slider 300 by two-direction operation of the two-direction switching knob 320 into contact with the fixed contact point of the circuit board 240, whereby a first circuit and a second circuit are formed respectively.
Reference numeral 310 is the light guiding member. The light guiding member 310 is formed of transparent synthetic resin (acrylate resin) of light transmitting property, and causes the mark 321 of the two-direction switching knob 320 to be illuminated by light from the single light source 220 via the two-direction slider 300. The light guiding member 310 is stored in a space between an upper surface of the inner partition plate 211 of the lower case 210 and a lower surface of the electric circuit board 240, and includes a light receiving surface 312 provided at one end of a light guiding member 311 and formed into a L-shape opposing to the single light source 220, and a rectangular light projecting member 313 provided at the other end of the light guiding member 311, and fitted into a small rectangular hole 241 of the circuit board 240 so as to oppose the lower surface of the two-direction slider 300.
The electric part with illumination in the prior art is configured as described above, and the operation thereof will be described below. In the operation of the two-direction switch, when the two-direction switching knob 320 located at the neutral position is moved toward the left (a dashed line in FIG. 14) or toward the right (a solid line in FIG. 14), the moving force of the two-direction switching knob 320 is transmitted to the two-direction slider 300, and the two-direction slider 300 slides in the same direction between the upper casing 200 and the circuit board 240, whereby the two-direction slider 300 is located at the first position or the second position.
The electric part with illumination in the prior art is configured in such a manner that the single light source 220 is illuminated, partial light from the single light source 220 passes through the small square through hole 241 of the electric circuit board 240 and advances from the lower surface to the upper surface of the transparent actuator 260, and reaches the four-direction marks 281 via the four-direction switching knob 280 to illuminate the four-direction mark 281. On the other hand, the remaining light passes through the light guiding member 311 from the light receiving surface and reaches the light projecting member 313, then, from the light projecting member 313, advances from the lower surface to the upper surface of the transparent two-direction slider 300, and reaches the two-direction mark 321 via the two-direction switching knob 320 to illuminate the two-direction mark 321.
Subsequently, another prior art will be described. As shown in FIG. 16, reference numeral 500 designates an illuminating section such as a light-emitting diode, reference numeral 501 designates an operating element (knob) having the illuminating section 500 inserted therein and retained at an upper end thereof, and reference numeral 502 designates a power feed sliding member provided on a lower surface of the operating element 501.
Then, the operating element 501, although not shown, is slidably stored in an enclosure with an upper portion of the operating element 501 projected therefrom. The power feed sliding member 502 of the operating element 501 slides on the fixed contact pattern formed on the bottom surface in the enclosure and is supplied with power.
In the slide-type electric part with illumination in the prior art as described above, since the longitudinal direction of the rectangular light projecting member 313 of the light guiding member 310 opposing the lower surface of the two-direction slider 300 coincides with the sliding direction of the two-direction slider 300, as shown in FIG. 14, even when the two-direction switching knob 320 is switched linearly to the left and right, the rectangular light projecting member 313 of the light conducting member 310 constantly opposes the lower surface of the two-direction slider 300 and supplies light from the single light source 220 to the two-direction switching knob 320 via the two-direction slider 300. Consequently, even when the sliding switch mechanism is used as the two-direction switch, the mark 321 of the two-direction switching knob 320 is constantly illuminated.
In the prior art, since the illumination is established over the entire area of the sliding movement of the two-direction slider 300, it is necessary to illuminate the unnecessary portion, and hence efficiency may be lowered. Also, since the two-direction slider 300 moves to the center, left and right positions, the distance from the light source 220 varies, and hence there was a problem that unevenness of illumination is generated.
Also, assembleability of the contact 370 of the two-direction switch was not good since the four coil springs 371, the two plate contacts 372, and the four contact point balls 373 are stored in a storage 302 formed on a lower surface of the slider 300 in a separate state.
The above-described problem does not exist in the slide-type electric parts in the arrangement shown in FIG. 16, since the illuminating section 500 is retained in the operating element 501 and is connected to the power feed patterns provided on the enclosure (fixed portion). However, in the arrangement of FIG. 16, there are problems that the cost is high since the illuminating section 500 is inserted into an upper portion of the operating element 501, the workability is low since the LED is inserted into the operating element 501 when assembling the LED as the illuminating section 500.